Studies are continuing on the interaction between adenoviruses and host cell control mechanisms by studying several situations in which the outcome of infection includes malignant cell transformation and/or abortive or productive virus replication. The chemical nature and mechanism of action of the viral inhibitory factor (VIF) from adenovirus-induced tumor cells is being studied, as is the relationship of its synthesis to virus replication. Purification and characterization of the adenovirus T antigen is being carried out in a parallel study. The mechanism by which arginine deprivation restricts adenovirus replication continues to be of interest, but the main thrust of this work is currently focusing on the effect of arginine deprivation on cellular DNA synthesis. A detailed analysis of the low molecular weight RNAs synthesized during adenovirus infection is continuing. BIBLIOGRAPHIC REFERENCES: Laughlin, C., and Strohl, W.A. Contrast in the effect of AMD on the DNA synthesized in adenovirus-infected human and hamster cells. Ann. Mtg. Amer. Soc. Micro., 1975. Rubio, V., Strohl, W.A., Laughlin, C., Silverstein, G., Weiss, E., Champe, P.C., and Schlesinger, R.W. Characterization and mechanism of action of the viral inhibitory factor (VIF) demonstrable in adenovirus-induced tumor cells. 3rd Intnl. Congress for Virology, Madrid, 1975.